# Hirth HM-504

- Type: Engine model (FAA registry)
- Registry code: 33701
- Manufacturer (registry): HIRTH
- Model: HM 504
- Engine type: Reciprocating
- Power: 100 hp
- Installed in: 3 registered aircraft
- Page: https://openairdocs.org/engine/hirth-hm-504

Model codes come from the FAA registry's reference file.

## ADs that may apply (OpenAirDocs)

Matched to this engine model by model name and maker. Each AD's applicability may narrow it by serial number, part number or equipment.

None matched.

## Registered aircraft (3)

- [N181BU](https://openairdocs.org/aircraft/N181BU): [Weeks Kermit A](https://openairdocs.org/faa-owner/WEEKS%20KERMIT%20A), [Polk City, FL](https://openairdocs.org/faa-place/FL/Polk%20City), S/N 461
- [N41455](https://openairdocs.org/aircraft/N41455): [Weeks Kermit](https://openairdocs.org/faa-owner/WEEKS%20KERMIT), [Polk City, FL](https://openairdocs.org/faa-place/FL/Polk%20City), S/N 78
- [N52DJ](https://openairdocs.org/aircraft/N52DJ): [Persons David A](https://openairdocs.org/faa-owner/PERSONS%20DAVID%20A), [Silver Lake, KS](https://openairdocs.org/faa-place/KS/Silver%20Lake), S/N CH21191CW0761

## NTSB investigations (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB NYC69F0088](https://openairdocs.org/ntsb/NYC69F0088), Jul 17, 1968: Scheibe SF27M (N6301), Hopewell Tnshp, NJ, substantial damage

## FAA accident and incident reports

None matched to aircraft with this engine model.

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